12021210021 has 4 divisors (see below), whose sum is σ = 16028280032. Its totient is φ = 8014140012.

The previous prime is 12021210013. The next prime is 12021210029. The reversal of 12021210021 is 12001212021.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (12021210013) and next prime (12021210029).

It is not a de Polignac number, because 12021210021 - 2³ = 12021210013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12021209979 and 12021210006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12021210029) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2003535001 + ... + 2003535006.

It is an arithmetic number, because the mean of its divisors is an integer number (4007070008).

Almost surely, 2^12021210021 is an apocalyptic number.

It is an amenable number.

12021210021 is a deficient number, since it is larger than the sum of its proper divisors (4007070011).

12021210021 is an equidigital number, since it uses as much as digits as its factorization.

12021210021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4007070010.

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 12021210021 its reverse (12001212021), we get a palindrome (24022422042).

The spelling of 12021210021 in words is "twelve billion, twenty-one million, two hundred ten thousand, twenty-one".